I dunno about my skill level in each but in order of how useful I feel:
Pyro (situational, when the rest of the team is being shit I feel ultra useless due to uncontested SGs owning my arse)
Soldier
Medic
All other classes - useless at them and I don't like playing as them, the heavy is too slow, I just get owned instantly, spy I haven't the patience, sniper is a lame concept - no fun at all, demo is a fiddley bastard to master, the scout was only made so valve could test at double speed, I loath playing engie, I fumble all the keys and I spend too long thinking about what to build and then it gets destroyed in 10 seconds and its a major downer and no fun at all.
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